Seat belt buckle



June 1966 E. H. KLOVE, JR.. ET AL 3,256,576

SEAT BELT BUCKLE Filed April 29, 1964 927 ATTORNEY United States Patent 3,256,576 SEAT BELT BUCKLE Edwin H. Klove, .112, and Joseph J. Magyar, Warren, Marvin A. Packett, Detroit, and Robert E. Meshew, Birmingham, Mich., assignors to General Motors Corporation, Detroit, Mich, a corporation of Delaware Filed Apr. 29, 1964, Ser. No. 363,430 13 (Ilaims. (Cl. 24-77) This invention relates in general to fastening devices and more particularly to a seat belt buckle adapted to be used in connection with the retention of passengers in airplanes, motor vehicles, or the like.

Seat belt buckles of some of the prior art have not been entirely satisfactory because thereis a tendency for many of the buckles to deform under excessive pressure conditions and allow the seat belts to slip- There is also a tendency for some of the. buckles to open due to decelerating forces upon the sudden stopping of the vehicle, the weight of the hinged portion of the buckle tending to throw the same forwardly and release the strap rendering the safety belt useless. In addition some of the buckles are likely to open upon the application of a force at the rear of the pivot of the latch releasing member causing inadvertent releasing of the buckle.

It is a general object of the present invention to provide a novel buckle for use with safety belts which is free of the above difiiculties and which is of simple rugged construction and reliable in use.

Other objects of the present invention are to provide a buckle which requires a minimum number of parts, is economical to manufacture, easy to assemble and relatively free of annoying rattle.

Another object of the present invention is to provide a buckle having a lock bar adapted to cooperate with a belt strap for maintaining the belt in an adjusted position so that the passenger is retained in his seat regardless of the intensity or magnitude of the decelerating force ap plied to the belt and to provide a reinforcement for the buckle structure under such conditions.

These and other objects and advantages of the present invention are obtained by a construction which includes a base member having a socket at one end thereof in which a latching pawl pivots. Resilient means normally bias the latching pawl toward a latching position where the pawl is adapted to be coupled to a locking plate. A cover member is provided with pawl releasing means and is attached to the base member by a cover spring which normally urges the cover member toward a closed position.

A more complete understanding of the present invention may be had from the following detailed description which should be read in conjunction with the drawings in which:

FIGURE 1 is a top plan view of the buckle with parts broken away;

FIGURE 2 is a sectional view taken along lines 22 of FIGURE 1;

FIGURE 3 is an exploded view of the buckle.

Referring now to the drawings, a preferred embodiment of the present invention is shown. The buckle is generally designated and comprises a base member 12 which is adjustably secured to a seat belt strap 14.

3,256,576 Patented June 21, 1966 ice The base 12 supports the locking pawl 16 which is biased toward the base to a locking position by the spring 18. A locking plate 20 is fixedly secured to the seat belt strap 22 and is adapted to be inserted into the base member 12 and be releasably coupled to the locking pawl 16 to join the straps 14 and 22. A cover member 24 is attached to the base member 12 by a gull-winged shaped spring 26 which also biases the cover toward a closed position. The cover member 24 is adapted to uncouple the pawl 16 from the locking plate 20 and thereby separate the straps 14 and 22. i

The base member 12 includes a generally horizontal bottom wall 28 having upstanding side walls 30 with inwardly-extending flanges 32 and upstanding end walls 34 and 36. The bottom wall 28 is provided with a generally rectangular indentation 38, integrally formed stop tabs 40 and a guide bridge 42.

The locking pawl 16 includes a tongue portion 44 having a transverse abutment edge 46. The forward portion of the pawl 16 comprises laterally-extending fingers 48 having downardly-projecting rounded extensions 50 adapted to engage a socket defined by the juncture of the forward end wall 34 and the bottom wall 28. The middle portion of the pawl 16 is provided with surfaces 52 adapted to engage the stop tabs 40 when the pawl is placed under load. The rearward section of the pawl 16 includes raised side portions 54 which are engaged by the cover 24 to release the buckle as will be explained hereinafter.

The pawl biasing spring 18 comprises an upper surface 56 abutting the underside of the flanges 32 of the base member 12 and a lower inclined surface 58 in engagement with the rearward portion of the locking pawl 16 so as to bias the pawl in a clockwise direction toward the bottom wall 28 of the base 12. The mid section 60 of the upper portion 56 extends over the end wall 34 of the base 12 to prevent longitudinal movement of the spring 18.

The cover member 24 is provided at its rearward portion with downwardly-extending side flanges 62 having integrally formed, outwardly-extending nibs 64. A pair of legs 66 having inwardly-extending feet 68 projects downwardly from the mid portion of the cover. The handle portion 70 extends forwardly of the end wall 34 and provides a smooth gripping surface for the cover 24. The spring 26 is provided with non-rotatable, laterallyextending arms which are recieved in the opening 72 in the side flanges 62 and is provided with a hook portion 74 which engages the end wall 36 to thereby attach the cover to the base 12. With the cover 24 attached to the base 12, the nibs 64 engage the underside of the flanges 32 and the inwardly-extending feet 68 extends between the pawl 16 and the bottom wall 28. The nibs 64 in conjunction with the spring 26 pivotally mount the cover 24 to the base 12. It should be noted that in the locked position there is a slight clearance between the pawl 16 and the feet 68 to insure that the feet do not rectangular in cross section with rounded forwardly and rearwardly facing end portions and rests on the bottom wall 28 with no portion thereof extending into the opening 75. Thus, when the straps 14 and 22 are subjected to extreme stress loads, the lock bar 76 moves rearwardly to the position shown in phantom lines wherein the belt strap 14 is wedged between the lower surface of the lock bar and the bottom wall 28. It should be noted that the lock bar 76 does not force the strap 14 against the edge 77 formed by the opening 75 in the conventional manner but rather moves rearwardly of the edge 77 to serve as a reinforcement for the rear cross member 78 of the base 12. Under extreme stress loads some conventional belt locking arrangements caused the base 12 to be deformed allowing slippage of the belt 14 thereby rendering the seat belt useless under these conditions. By merely rotating the base 12 approximately 90 the belt strap 14 may be lengthened while it is only necessary to pull on the free end of the strap to shorten the length.

In operation, the locking plate 20 which includes a transverse abutment edge 79 formed by a rectangular opening 80 is inserted through a transverse slot 82 in the end wall 34 and engages the tongue portion 44 of the pawl 16 thus raising the pawl in a counterclockwise direction against the spring 18 until the tongue portion 44 engages the opening 80 at which time the pawl returns to a locked position. When the locking plate 20 is fully inserted, it extends through the guide bridge 42 to maintain alignment of the locking plate and the base 12. Any force on the seat belt straps 14 and 22 engages the edge 46 of the tongue 44 and the edge 79 of the locking plate 20 and tends to rotate the pawl 16 slightly in a clockwise direction while driving the surfaces 52 into engagement with the stop tabs 40. When it is desired to release the buckle, the user grasps the handle portion 70 and rotates the cover 24 in a clockwise direction about the transverse axis passing through the nibs 64. As the cover 24 raises, the feet 68 engage the surface 54 on the pawl 16 to rotate the pawl in a counterclockwise direction against the bias of the spring 18 at the same time the laterally-extending arms on the spring 26 are forced downwardly as a result of the engagement of the nibs 64 with the underside of the flanges 32 with a torsional force also being applied thereto. When the tongue member 44 clears the opening 80 in the locking plate 20, the locking plate may be removed from the base 12. Upon release of the cover 24, the spring 18, acting through the pawl 16, and the spring cover 26 rotate the cover 24 in a counterclockwise direction to the position shown in FIG- URE 2. As indicated previously, however, the spring 18 does not return the cover completely since the tongue portion 44 of the pawl 16 will engage the bottom Wall 28 before the cover 24 is fully returned to the closed position. The spring 26, however, will continue to exert a force on the cover 24 to return the cover to the fully closed position. It should be noted that while the cover 24 may be easily moved to a release position by pulling upon the handle portion 70, the reverse is not so, i.e., pressure on the rear portion of the cover 24 does not cause the cover to be rotated to a release position. Rather, the spring 26 flexes downwardly where the flanges 62 engage the bottom wall 28 to prevent further movement of the handle portion 70 away from the bottom wall 28. Thus it will be seen that the buckle is not subject to inadvertent release from the application of a force at or near the pivot axis of the cover.

The construction and arrangement of the parts of the buckle allow rapid assembly. After the lock bar 76 is placed in position, the pawl 16 is placed in position with the extensions 50 pivotally engaging the socket at the forward end of the buckle. Spring 18 is then inserted from the rear portion of the buckle beneath the flanges 32 and biases a pawl 16 toward the bottom wall 28. The mid section 60 is snapped into engagement with the end wall 34 to maintain the spring 18 in position. Spring 26 is 4 then connected with the cover 24 and snapped into position at the reaward end of the base 12 with the nibs 64 extending beneath the flange 32 and the hooked portion 74 coupled to the end wall 36.

The embodiment of the invention as disclosed herein is for illustrative purposes only and the scope of the invention is intended to be limited only by the following claims.

We claim:

1. A seat belt buckle comprising a base member, a latching pawl supported by said base member, said base member forming a socket at one end thereof in which said pawl pivots, a locking plate releasably coupled to said pawl, resilient means normally, yieldingly urging said pawl toward a latching position, a cover member including side flanges and pawl-releasing means extending between said pawl and said base member, a cover spring member supported by said base and extending through said side flanges to pivotally mount said cover member at the end opposite said one end of said base and to normally, yieldingly urge said cover toward a closed position.

2. A seat belt buckle comprising a base member, a latching pawl supported by said base member, said base member forming a socket at one end thereof in which said pawl pivots, a locking plate releasably coupled to said pawl, resilient means normally, yieldingly urging said pawl in a clockwise direction, a cover member including side flanges and pawl-releasing means extending between said pawl and said base member, a cover spring member supported by said base and extending through said side flanges to pivotally mount said cover at the end opposite said one end of said base and to normally, yieldingly urge said cover toward a closed position.

3. A seat belt buckle comprising a base member including a bottom wall and upstanding side walls forming a channel and having an opening therein, a lock bar supported by said bottom wall in sliding non-rotatable engagement in said bottom Wall, a locking plate, a first belt strap coupled to said locking plate, latch means supported by said base member for releasably coupling said locking plate to said base member, a second belt strap extending through said opening and forming a loop around said lock bar, said lock bar being freely movable in a rearward direction, the rearward movement being limited only by the confines of said loop, whereby at least a portion of said lock bar moves rearwardly of said opening under load to prevent lengthening of said belt strap and to reinforce said bottom wall.

4. A seat belt buckle as defined in claim 1 wherein the base member includes an opening adapted to receive the end portion of a seat belt strap, a movable lock bar within said casing about which said strap is adapted to pass, said lock bar being movable rearwardly beyond the rear edge of said opening for locking said strap against lengthening and to reinforce said base member against deformation.

5. A seat belt buckle comprising a base member having side walls with inwardly-extending flanges, a latching pawl supported by said base member, said base member forming a socket at one end thereof in which said pawl pivots, a locking plate releasably coupled to said pawl, resilient means normally, yieldingly urging said pawl in a clockwise direction, a cover member including guide flanges and pawl releasing means extending between said pawl and said base and having laterally-projecting nibs, a cover spring member supported by said base member and extending through said side flanges to bias said nibs into engagement with the underside of the flanges of said base member to thereby pivotally mount said cover at the opposite end of said base member and to normally, yieldingly urge said cover in a counterclockwise direction.

6. A seat belt buckle as defined in claim 5 wherein the base member includes an opening adapted to receive the end portion of a seat belt strap, a movable lock bar within said casing about which said strap is adapted to pass, said lock bar being movable rearwardly beyond the rear edge of said opening for locking said strap against lengthening and to reinforce said base member against deformation.

7. A seat belt buckle comprising a base member, a latching pawl supported by said base member, said base member forming a socket at one end thereof in which said pawl pivots, a locking plate releasably coupled to said pawl, resilient means normally, yieldingly urging said pawl toward a latching position, a cover member including side flanges and pawl-releasing means extending between said pawl and said base member and including laterally-projecting nibs, a cover spring member having a lower portion aflixed to said base and laterally-projecting arms extending through the side flanges of said cover rearwardly of said nibs and cooperating with said nibs to pivotally mount said cover to said base while biasing said cover toward a closed position. v

8. A seat belt buckle comprising a base member including a bottom wall having upstanding side walls and end walls with the side walls including inwardly-extending flanges, one of said end Walls and said bottom wall forming a socket, a latching pawl supported by said base member and adapted to pivot in said socket, a locking plate releasably coupled to said pawl, resilient means normally, yieldingly urging said pawl in a clockwise direction toward said bottom wall, a cover member including side flanges and pawl-releasing means extending between said pawl and said bottom wall and including laterallyprojecting nibs extending between said flanges of said side walls and said bottom wall, a cover spring member cooperating with said nibs to pivotally mount said cover to said base and including a lower portion abutting said bottom wall and having upwardly-extending side portions terminating in laterally-extending arms which protrude through the side flanges of the cover, rearwardly of the 'nibs to bias the nibs into engagement with the underside of the flanges of said side walls and to bias the cover in a counterclockwise direction, said lower portion also including a rearwardly-extending tab engaging the other end wall to maintain the position of said cover spring relative to the end wall.

9. A seat belt buckle for fastening the free ends of a seat belt comprising-a base member adjustably secured to one of said free ends and having a bottom wall with upstanding side walls and'an end wall, the side walls having inwardly-extending flanges, a slot extending through said end wall, said end wall and said bottom wall forming a socket, a locking plate secured to the other free end of said seat belt and including a transverse abutment edge, a locking pawl pivotally engaging said socket and including a tongue portion adapted to engage said transverse abutment edge, resilient means extending between said base and said pawl to normally, yieldingly urge said pawl toward a latching position, a cover member having pawlreleasing means extending between said pawl and said bottom wall and including downwardly-extending side flanges and laterally-extending nibs, a cover spring member cooperating with said nibs to pivotally mount said cover and having a lower portion affixed to said base and laterally-projecting fingers extending through the side flanges of said cover rearwardly of said nibs to bias said nibs into engagement with said flanges of said side walls while biasing said cover toward a closed position.

10. A seat belt buckle as defined in claim 9 wherein the base member includes an opening adapted to receive the end portion of a seat belt strap, a movable lock bar within said casing about which said strap is adapted to pass, said lock bar being movable rearwardly beyond the rear edge of said opening for locking said strap against lengthening and to reinforce said base member against deformation.

11. A seat belt buckle comprising a base member including a bottom wall having upstanding side walls and end walls with the side walls including inwardly-extending flanges, one of said end walls and said bottom wall forming a socket, a latching pawl supported by said base member and adapted to pivot in said socket, a locking plate releasably coupled to said pawl, resilient meansnormally, yieldingly urging said pawl in a clockwise direction toward said bottom wall, a cover member including side flanges and pawl-releasing means extending between said pawl and said bottom wall and including laterallyprojecting nibs extending between said flanges of said side walls and said bottom wall, a cover spring member cooperating with said nibs to pivotally mount said cover adjacent the other end wall relative to said base and including a lower portion abutting said bottom wall and upwardly-extending side portions terminating in laterallyextending arms which protrude through the side flanges of the cover rearwardly of the nibs to bias the nibs into engagement with the underside of said flanges of said side wall and to bias the cover toward a closed position, said lower portion also including a rearwardly-extending tab engaging the other end wall to maintain the position of said cover spring relative to the end wall.

12. A buckle comprising a base member having a bottom wall, upstanding side walls and end walls, the side walls having inwardly-extending flanges with one of the end walls provided with an aperture, a locking plate including a transverse abutment edge and adapted to be inserted through said aperture, a locking pawl including a tongue portion adapted to engage said transverse abutment edge and laterally-extending fingers terminating in transverse rounded projections in engagement with a socket defined by the bottom wall and said one of said end walls to allow pivotal movement of said pawl, resilient means extending between said flanges of said side walls and said pawl and including a catch member in engagement with said one of said end walls to normally, yieldingly urge said pawl toward a latching position, a cover member overlying said base member and extending between the extremities of said flanges and having a handle portion extending beyond said one of said end walls, said cover member having a pair of downwardly-projecting legs with inwardly-projecting feet extending between said pawl and said bottom wall, said cover member also having a pair of transversely-extending side flanges and a pair of laterally-extending nibs engaging the underside of said flanges of said side walls, a flexible member extending through said side flanges and having a portion in engagement with said bottom wall and another portion in engagement with the other of said end walls and cooperating with said nibs to provide a pivotal mounting for said cover whereby pivoting of said cover causes said feet to lift said pawl to disengage said tongue portion from said abutment edge.

13. A buckle comprising a base member having a bottom wall with transversely-extending side walls and end walls, the side walls having inwardly-extending flanges, one of the end walls provided with a slot, said one of said end walls and said bottom wall forming a socket, a pair of stop tabs formed in said bottom wall and extending upwardly therefrom, a locking plate having a transverse abutment edge and adapted to be inserted insaid slot, a latching pawl having a tongue portion extending toward said bottom wall and adapted to engage said transverse abutment edge, a rounded end portion in engagement with said socket and a portion in engagement with said stop tabs, a spring member between said pawl and said base member and normally, yieldingly urging said pawl toward said bottom wall, a cover member having pawl-engaging means extending between said pawl and said bottom wall and including laterally-extending nibs engaging the underside of said flanges, a cover spring member extending between said bottom wall and said cover and biasing said nibs into engagement with said flanges to provide a pivotal mounting for said cover memposition.

7 8 her while normally biasing said cover toward a closed FOREIGN PATENTS References Cited by the Examiner gig: UNITED STATES PATENTS 655,887 8/ 1951 Great Britain. 10/1957 R 24 197 5 939,112 10/1963 Great Britain.

10/1957 G 1d t 2477 V1959 g i WILLIAM FELDMAN, Primary Exammer. 11/ 1964 Warner 24196 BERNARD A. GELAK, Examiner. 

1. A SHEET BELT BUCKLE COMPRISING A BASE MEMBER, A LATCHING PAWL SUPPORTED BY SAID BASE MEMBER, SAID BASE MEMBER FORMING A SOCKET AT ONE END THEREOF IN WHICH SAID PAWL PIVOTS, A LOCKING PLATE RELEASABLY COUPLED TO SAID PAWL, RESILIENT MEANS NORMALLY, YIELDINGLY URGING SAID PAWL TOWARD A LATCHING POSITION, A COVER MEMBER INCLUDING SIDE FLANGES AND PAWL-RELEASING MEANS EXTENDING BETWEEN SAID PAWL AND SAID BASE MEMBER, A COVER SPRING MEMBER SUPPORTED BY SAID BASE AND EXTENDING THROUGH SAID SIDE FLANGES TO PIVOTALLY MOUNT SAID COVER MEMBER AT THE END OPPOSITE SAID ONE END OF SAID BASE AND TO NORMALLY, YIELDINGLY URGE SAID COVER TOWARD A CLOSED POSITION. 